Ozonation characteristics of bisphenol a in water

Abstract

Ozonation characteristics of bisphenol A were investigated as a function of gaseous ozone dose, initial concentration of bisphenol A, pH, radical scavenger (tert-butanol), and radical initiator (hydrogen peroxide). The ozonation led to a complete removal of bisphenol A in water within a certain period of time. The overall rate of the ozonation linearly increased with the ozone dose. The stoichiometry in the ozonation of bisphenol A was found to be 1.5 - 1.8 mole of ozone per mole of bisphenol A. The direct reaction rate constants were 1.3 x 10(4) M(-1)s(-1) for bisphenol A (at pH = 2) and 1.6 x 10(9) M(-1)s(-1) for dissociated bisphenol A (at pH = 12). Bisphenol A degraded via the direct reaction with molecular ozone in the pH range from 2 to 12. Degradation by OH radical was minor even at pH = 12. The overall degradation rate in heterogeneous conditions was independent of pH as it was limited by ozone mass transfer rate. Use of hydrogen peroxide did not alter the main degradation route and the molecular ozone remained a principal oxidant as a substantial portion of the OH radical is scavenged by hydrogen peroxide. Effective ozone mass transfer may appear essential to enhance the ozonation kinetics of bisphenol A.

Ozonation of aqueous solution containing bisphenol A: Effect of operational parameters

“…Furthermore, at pH value of 7.0 bicarbonate ion which has a lower reactivity towards • OH compared with carbonate ion is a predominate species. In addition, the reactivity of bicarbonate and carbonate ions with aqueous ozone, 1 × 10 −2 and <1 × 10 −2 M −1 s −1 [42], respectively, is significantly lower than that of BPA reported in the literature: 1.3 × 10 4 M −1 s −1 [29] and 2.7 × 10 6 M −1 s −1 [31]. achieving about 79 and 92% at pH values of 5.0 and 7.0, respectively.…”

“…The air-to-water ratio must be very high to effectively remove BPA, which increases the cost of treatment. Non-conventional treatment techniques have been examined for the degradation of BPA, including TiO 2 photocatalyst [25], photo-Fenton process [26], sonochemical reaction [27], UV photolysis [28], and ozonation [29][30][31].…”

Removal of Endocrine Disruptors from Urban Wastewater by Advanced Oxidation Processes (AOPs): A Review

“…This trend was not confirmed by the study of Lee et al [58], dealing with bisphenol A (BPA) ozonation at pH ranging between 2 and 12. Authors found that degradation rate was sensitive and proportional to the ozone feed rate, but insensitive to pH and BPA concentration.…”

Synthetic endocrine disruptors in the environment and water remediation by advanced oxidation processes

“…The following discussion covers a critical review of published research on ozonebased destruction of BPA in water. Lee et al (2003) studied the degradation of BPA at pH ¼ 2, 7 and 12 and found that the rate was sensitive and proportional to the ozone feed rate, but insensitive to pH and the concentration of BPA. They found that even at extreme alkaline conditions (e.g.…”